#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string>
#include <iostream>

int main()
{
    std::string str;
    str.reserve(256);
    write(4,str.c_str(),str.size());
    perror("write");
    return 0;
}